Clamp joint



Aug. 17, 1943.

F. M KINCAID, JR

CLAMP JOI NT Filed Jan. 31

INVENTOR Frank MlfnncaziJ ATTORNEY S j ggszases OI I Frank mq e aie. are, ltlountain 'I-iakes,--N. J assi-gnor' to wright Aeronautical corpora-home 'corporatien of New York- 1 T Application rairiie yfsi, 194i, S'e'rialNo. 375 .742

p v g V toners. (Cl. 287124) V v This rinventiongrelates rte j j t anaem a der stressthegpartition.L5 also.iorr'ni i anabrularly to, joints wherein a shaft'is litted to an ern ment for'aspaber .l 6 and forjalnutl 1.. Ime'spaeerbracing member and whergjnibhg s haft and i5 is thelhbllQlM.Hfandfitfilfikeil herare-secured to :one', another ;aga-inst -r'elative at the left endlof the spacer and withinlthe displacement. ,A -,,partioular environment in 5 hollow hi are a'phi'ralityof-cuppedwashers.l8

which? the provisions of the invention may he Wh LQ G Ve idesiaeeltoward ithefs'pacerjlfi. useful is.mthe-clampjointbetweeha cranlrpin These washers are ehamfered atth'ei'r edges as and crankchesk in a composite engin ankshown in eith'enFigs'. 5 or 6. and are iorznedwith shaft, particularly, in singl doub gt h Qw f anoutsid'ediameter such thatthey fit closely crankshafts of radial cylinder aircraft engines 10 to the bore; when in the..,u'nstressed condition.

Such shafts, according to conventional practice, A bolt- 26 is passed throughf th'e stack of washers are built .up of a .crankcheek ,and a;crankpin seth t e Sp '15 and threllg ea l t cured to one another either :by. .snlined 'connecmentf-ifi, andlis e gag d y t e'nut I'll -Up 0 tion or byclampingthe cheek aroundthemaul; tightening of theinut' ilgthe head 21 of the belt I pin by means of a clamp bolt; in the cheek. The engages the left end washer l8 adjacentitheedge present invention contemplatesexpanding the of vthewas e IeL-e t ewholestack er wash- .crankpim which is, hollow, --outwardly into clamp- 6 's s gradually. fl t ened .by the application of ing engagement with the, crankcheek. v V i axial force from their eiip edform to a substan Further objects of the inventiqn,-in addition 2 tially planeform, as shown in Fig. l. As-axial to that just noted, consist 'in the provision .of p u s 'hl p e t th e 0f Was s; fi d means for expanding .a' sleeve into-clamping 1e11- .aSth Iy approachaplan i u ,t yh t ly gagement with an embracing member; to provide become lar er i eve'iall diameter ahdihu's' b n means for expanding a hollow member under ip h the inner walI off the oranki illhi'arid asstress intensities within the elastic-limit of the th d rth l creases,th c r a k material, into clampingengagementwithangem- W D Q d d y i'IitO fi e hp i e vpin-crankche'ek joint;

. ternate form of joint;

bracing member.; -to provide.expanding-means g emeh W th' a) lc rahkclieelifniember 24 em consisting. of nested cupped elements ,within a bracing t t e o the kp i, he crankhollow sleeve which may be deformed for sin- D be 'c e fi initially to the b'ore'in w crease in their diam'eterby the,applicationof V e lera hkohe'ekQ "Said crankcheek carries "a axial pressure to the cupped elements, suchflin.- -3 crankshaft: journal 25 coaxial with h l 9 crease indiameter concurrently enforcing .radi- Itis deemed t r Withinthe abilities (if one ally outward expansion ofithe sleeve element; l in theilaft t calculat'e .tlie clea qn e Aiurther object is to provide improvements neeeseery t ee mb y Of theseveral co p n s in crankpin construction, including'theprovision in d r 9 gafi ii malhpi e fi j of reinforcing meanstending to hold a :hollow 5 en the hP hf leIld the crankche'e'k ilil. crankpin incircular form, z v H H w 7 Further objects ofsthe invention will; become di io to the size and. degree ofj pp s 0f apparentinreading the-descriptio'n'below inconthe Washers 3 W ll be important fa'oto i i :denection'with the drawing, in iwhichz termining e tighthese O t e fi le t S Fig. 1 is a longitudinal section throughfarcrank .40 n id h the, s e im s d y fl e ing the cuppedwashers shouldbe withinth'e Ob vious1y,-the thickness of the crankpinwall in t Fig. 2 is a fragmentary longitudinal sectionqof e t s imi ithema ri 0 h t e; washthe joint of :Fig. 1' prior to clamping; r t ra kpim q the erankcheek, in-prdel Fig. 3 is a longitudinalsection through anal-I th 1d a em ly may, -be efiected when desired Fig. 4 is a longitudinal searcher the joint of leh s i l-het efiimi is ed. Fig. 3 before clamping; and.

v4 5 andin orderthatithestreng-th.eitheseVeral cem- It is apparent that .the stack washersg le 'Figs. 5"and s are enlarged detailednsections t i .a h c neses l st ntiaiiyt egsame asthe' showing alternatemodes of formingcertain .eleh sne e t h k n e ,t u am ments of the joint. '3 V Referring first toFigs. 1 and 2, it indicates a n ssj t r n h e nd W t x ndl pe ing action may be attained throughout thethiclg-f crankshaft journal having an integral :crankth erenkP n-e th s s i s enst he e cheek H from'which an 'integral crankpin 5L2 clampmg action i unnecessary, extends in parallelism mth thejournal [0. The "Fi -f a 4 Sh w 1 m alternatetype 0f..l'

pin 12 is hollow as'at l3 for lightnessiand is wherein two s d :c lieh eks 30 andilare hollow at its free end as'at; T4 for a purpose D Q i edW thaIined,boresgjlengagedby holshortly to be described, the hollows I3 and M be- 1 0 te kpi Two-stacks ,ofiw s e fs 3 are ing separated by an annular partition [5 midway utilized, One for enforcing clamping engagement 'of the crankpin journal to provide for reinforce the p h 3 With the Cheek d the ment to assure circular form of the journal unother for ing'clamp g engagement of the crankpin 33 with the cheek 3!. Each stack comprises a first plurality of washers l8 whose concave facesare opposite a second plurality of washers whose concave facesin turn face toward the first plurality. The tightening bolt for this arrangement consists of a shank 36 having an integral abutment 31 engaging theinner edge I vex side of the washer at the other end of the washers 18 are flattened and effect clamping beasaasee V hollow shaft in the plane of each member, and means to uncup or flatten said washer sets jointly for peripheral binding engagement with the shaft and thereby to expand the shaft ends into binding engagement with said members, said uncupping means'comprising end-to-end elements relatively axially movable and constrained against relative rotation, and screw devices engaging the 1' 0'. set. The abutments 37 and 38 are brought ton gether by the means of a nut 39 whereupon the tween the crankpin and crankcheek as above de-j scribed, The other, set of cupped washers are clampedin similar manner by a bolt 40 having an inner integral abutment ll engaging the end washer of the other set of washers. Between the abutments 31 and 4|, the bolts 36 and 40 are sleeved, one over theother, as at 43,this 's1eev-' ing connection allowing of free axial movement of the'bolts 36 and 40 and preventing .relative rotation therebetween. 'I'hus, when nuts 39 and 39"are concurrently tightened, the two washer sets 34 will be drawn up axially without displacing their edges from the proper axial re lationship with respect to the crankcheeks 38 and 3| with which respective sets are substantially coplanar. 1 I

As mentioned previously, the washers it are a chamfered slightly at their outer edges, either in a spherical form as shown at 46 in Fig. 5, or with small-radii at the washer edges as shown at 47 in Figg'G. By this breaking ofthe' edges" a good initial fit may "be assuredbetween the washer and the 'crankpinbore'andadditionally, as the washer is flattened, its edge will nottend to scuff the surface of the crankpin. i j i Although the invention has been shown as'applied to a'crankpin to crankcheek joint; it' is obvious that the'teachings of the'invention maybe applied at any jointbetween a hollow'member and an embracing member, and it is intended that the claims below cover any such altern'ate arrangement or environment for the invention.

While I have described my invention in detail in its present'preferred embodiment, it will be obvious to'those skilled in the art, after understanding my invention, that various changes and modifications may be made therein without departing from the spirit or scope thereof. I aim" in the appended claims to cover all'suc'h modifications and changes. I V I? I claim as my invention: g

1. In a clamp joint between a member having a bore and a hollow shaft fittedto the bore for free assembly with the member, a plurality of dished chamfered edge annular washers disposed in the hollow shaft, a reaction means Within the shaft engaging the outer edge -'of one'of the end Washers oi the plurality on" its concave face to properly position the washers within said shaft, and a member passing through the holes of the washers engaging said reaction means and engaging 'the hole edge of the other end Washer of a plurality on its convex face, said-member being axially movable toward said reaction mean to flatten said washers. I! r 2. In a Iclamp joint betweena hollow shaft and a pair of spaced members having alined bores, said shaft being fitted to saidbores and bridging said members,-a set of cuppedwasherswithin the outer. ends of said elements for clamping the washers ofe'ach set.

3. ,In a clamp joint between a hollow shaft and a pair of spaced members having alined bores, said shaft being fitted to said bores and bridging said members, a set of cupped washers within the hollow shaft in the plane of each member, and means to uncup or flatten said washer sets jointly for peripheralbinding engagement with the shaft and thereby to expand theshaft ends into binding engagement with said members, said .uncupping means comprising end-to-end elements relatively axially movable and constrained against relative rotation, and screw devices engaging the outer ends of said elements for clamping the 'Washers of each set, said pin having a central internal' annular rib between said members to stiffen the shaft. 7

' 4. In a clamp joint between a hollow shaft and a pair of spaced members having alined bores, said shaft being fitted tosaid bores and bridging said members, a set of cupped washers .within the hollow shaft in the'planeof each member, and means to uncup' or flatten saidwashers, said means comprising a pair of members each extending'through' one of said sets of washers, said members being relatively axially movable but constrained against relative rotation.

5. In a clamp joint between a hollow element and a member having a bore within which said .element is fitted, a stack of initially dished-shaped washers fitted within said hollow element, annular rib means rigidly disposed within said hollow element and cooperable with the periphery :of the concave end of the stack of dished-shaped washers for properlylocating'said washerswithin said element, an axially movable screwnieans ex-,

tending through the washers and cooperating with said annular rib means for drawing the central portion of. said Washers toward said rib means'to'fiatten said washers andto enforce movement ofthe peripheries of said washers rae dially outward into binding engagement with the hollow element, said element being radially extended by washer pressureinto binding-engage,- ment with said member., ,r

6. In a clamp joint between a hollow element and a member having a borewithin which said element is fitted, a stackof initially dished-shaped washers fitted within said hollow elementstop means disposed within said hollow elementand cooperable with the periphery of the, concave end of the stack of dished-shaped. washers, to properly locate said washers within said element, a movable member extending. through the washers and cooperating with :said stop means for drawing the central portions of said washers toward said stop means to, flatten said washers and to enforce movement of the peripheries of said washers, radially. outward into binding engagement ,Withthe hollow, element, saidelementbeing radially extended by washer pressure into binding engagement with said member, 7

. 1, 4 .FR ANK' MVKINCAID, JR. 

